From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6098C433E0 for ; Tue, 2 Feb 2021 17:35:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9F8B764E9C for ; Tue, 2 Feb 2021 17:35:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237621AbhBBRfh (ORCPT ); Tue, 2 Feb 2021 12:35:37 -0500 Received: from mail.kernel.org ([198.145.29.99]:46918 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237619AbhBBRdQ (ORCPT ); Tue, 2 Feb 2021 12:33:16 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id DCFFA64E9C; Tue, 2 Feb 2021 17:32:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612287157; bh=M04SyJQ3T5b23EF8TLLqUAMtt12G2frfLwd0wJ9JWQ8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=lRxlVEhEKodVWMocEvyPe3sQzPs9mOXAwDb6/SMLVVqNyrCjd0DOQWHR2btcxPiZp ZZrdMff5hUFPzoiDew4VHSK8uKINZp301DKBfW8QeMlt+hbPeYsjbp1BMBFkQsz/oK 5HYbBmDU1+URsjyx5sUmxP1Lc8FxtIXQ+KnAg9q1H7dVz9ShgMVk77gDTFQPyfYg6U uYMUS2mRfmmoiTw4REPX9VFT3Jl+u5VGphRmwT1tE8ykU0DWSso2WCsZk+zEI90jwe hKevJyTOxMz6cVS4YFHneY15O6c0P4z777MnE1SnAobeFTPWEHTrdmts4sqhghnDVJ 73iULHZRVzdug== Date: Tue, 2 Feb 2021 19:32:30 +0200 From: Jarkko Sakkinen To: Kai Huang Cc: linux-sgx@vger.kernel.org, kvm@vger.kernel.org, x86@kernel.org, seanjc@google.com, luto@kernel.org, dave.hansen@intel.com, haitao.huang@intel.com, pbonzini@redhat.com, bp@alien8.de, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com Subject: Re: [RFC PATCH v3 08/27] x86/sgx: Initialize virtual EPC driver even when SGX driver is disabled Message-ID: References: <5076ed2c486ac33bfd87dc0e17047a1673692b53.1611634586.git.kai.huang@intel.com> <20210201184040.646ea9923c2119c205b3378d@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210201184040.646ea9923c2119c205b3378d@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Mon, Feb 01, 2021 at 06:40:40PM +1300, Kai Huang wrote: > On Sat, 30 Jan 2021 16:45:43 +0200 Jarkko Sakkinen wrote: > > On Tue, Jan 26, 2021 at 10:31:00PM +1300, Kai Huang wrote: > > > Modify sgx_init() to always try to initialize the virtual EPC driver, > > > even if the bare-metal SGX driver is disabled. The bare-metal driver > > > might be disabled if SGX Launch Control is in locked mode, or not > > > supported in the hardware at all. This allows (non-Linux) guests that > > > support non-LC configurations to use SGX. > > > > > > Signed-off-by: Kai Huang > > > --- > > > v2->v3: > > > > > > - Changed from sgx_virt_epc_init() to sgx_vepc_init(). > > > > > > --- > > > arch/x86/kernel/cpu/sgx/main.c | 4 +++- > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c > > > index 21c2ffa13870..93d249f7bff3 100644 > > > --- a/arch/x86/kernel/cpu/sgx/main.c > > > +++ b/arch/x86/kernel/cpu/sgx/main.c > > > @@ -12,6 +12,7 @@ > > > #include "driver.h" > > > #include "encl.h" > > > #include "encls.h" > > > +#include "virt.h" > > > > > > struct sgx_epc_section sgx_epc_sections[SGX_MAX_EPC_SECTIONS]; > > > static int sgx_nr_epc_sections; > > > @@ -712,7 +713,8 @@ static int __init sgx_init(void) > > > goto err_page_cache; > > > } > > > > > > - ret = sgx_drv_init(); > > > + /* Success if the native *or* virtual EPC driver initialized cleanly. */ > > > + ret = !!sgx_drv_init() & !!sgx_vepc_init(); > > > > If would create more dumb code and just add > > > > ret = sgx_vepc_init() > > if (ret) > > goto err_kthread; > > Do you mean you want below? > > ret = sgx_drv_init(); > ret = sgx_vepc_init(); > if (ret) > goto err_kthread; > > This was Sean's original code, but Dave didn't like it. I think it should be like: ret = sgx_drv_init(); if (ret) pr_warn("Driver initialization failed with %d\n", ret); ret = sgx_vepc_init(); if (ret) goto err_kthread; There is problem here anyhow. I.e. -ENODEV's from sgx_drv_init(). I think how driver.c should be changed would be just to return 0 in the places where it now return -ENODEV. Consider "not initialized" as a successful initialization. /Jarkko